How to Check Image DPI on Windows and Mac (and Why It Lies)
August 3, 2026
Both Windows and macOS will happily show you a DPI number for any image. Here’s where to find it — and then the more useful part, which is why that number is a poor guide to whether your file will actually print sharp.
Windows 11: File Explorer
- Right-click the image and choose Properties.
- Open the Details tab.
- Read the fields under Image.
On a Windows 11 machine, File Explorer shows these fields for a PNG:
| Field | Example value |
|---|---|
| Dimensions | 1200 x 630 |
| Width | 1200 pixels |
| Height | 630 pixels |
| Horizontal resolution | 96 dpi |
| Vertical resolution | 96 dpi |
| Bit depth | 32 |
Horizontal resolution and Vertical resolution are the DPI fields. Most guides stop here and tell you this is your image’s DPI. That’s the part worth questioning.
macOS: Preview
Open the image in Preview, then open the Inspector — either the Info button in the toolbar, or Tools → Show Inspector. Apple’s documentation describes the Inspector as showing “information about a document or image, such as file size, the author name, and the image resolution.”
You’ll get dimensions in pixels and a resolution figure, the same pair Windows shows.
Why that number usually lies
The DPI shown for a file is metadata — a tag written by whatever software exported it, if it wrote one at all. It’s a stated intention about print size. It is not a property of the pixels, and nothing enforces it.
It can be weaker than that. Plenty of files carry no resolution tag whatsoever: PNG keeps it in an optional chunk that many exporters simply leave out. The file in the table above is exactly that case — it contains no resolution data at all, yet Explorer still displays 96 dpi. We checked by writing a real 300 dpi tag into a copy with byte-identical pixels: the same image then reports 300 dpi, with not one pixel changed.
So the number can be an unenforced tag, or it can be supplied by the viewer for a file that never claimed anything.
What actually decides sharpness is simple arithmetic:
Effective DPI = pixel dimension ÷ print size in inches
Two cases make the point:
- A file tagged 72 DPI at 3000 × 2400 pixels, printed at 10 × 8 inches, delivers 3000 ÷ 10 = 300 effective DPI. It prints beautifully, despite the scary tag.
- A file tagged 300 DPI at 800 × 640 pixels, printed at the same 10 × 8 inches, delivers 800 ÷ 10 = 80 effective DPI. It prints soft and blocky, despite the reassuring tag.
Same tags, opposite outcomes. The tag never entered the calculation.
This is why “is my image 300 DPI?” is not answerable from the file alone. The honest answer is another question: at what size are you printing it? A 3000 × 2400 file is 300 DPI at 10 × 8 inches, 150 DPI at 20 × 16, and 75 DPI at 40 × 32. One file, three answers.
When the metadata does matter
It isn’t always noise. Some print workflows read the embedded resolution to decide a default placement size, so a file tagged 72 DPI can land on the page far larger than you intended until someone rescales it. That’s a layout inconvenience, not a quality problem — the pixels are unchanged.
So treat the tag as a hint at best — it reflects what some exporter assumed, or nothing at all — and treat pixels ÷ print size as the truth.
What to do instead
Work backwards from the finished print:
- Decide the physical size you’re selling — 8 × 10 inches, A4, 24 × 36.
- Multiply each dimension by 300 to get the pixels you need.
- Compare that against the pixel dimensions Windows or Preview just showed you.
An 8 × 10 inch print needs 2400 × 3000 pixels. If your file is smaller than that, no metadata edit will fix it, and no “upscale” that invents pixels will match real detail.
Coming out the other side — a file far larger than the print needs — is a nicer problem, and worth solving too: an oversized export wastes upload allowance and download time for no visible gain. Our image resizer brings it down to the pixel dimensions you actually need. If the image is headed for an Etsy listing rather than a print, the listing image checker tests it against Etsy’s own photo requirements.
Our DPI checker does step 3 for you: it reads the real pixel dimensions, asks what size you intend to print, and reports the effective DPI — the number that decides the outcome. The print size calculator runs it the other direction, from a print size to the pixels required.
If you’re exporting from Canva specifically, how to check DPI in Canva covers getting a genuine 300 DPI file out of it. For where the 300 figure comes from and when a lower number is fine, see what DPI printables should be.
The short version
Windows Properties → Details and macOS Preview’s Inspector both show a DPI tag. It’s metadata, and it can say anything. Divide your pixel dimensions by your intended print size in inches — that result is the only DPI that reaches the paper.